Animals That Can Think
Ringo
The evolutionary record suggests that dogs descended from wolves, but that does little to explain the symbiotic relationship that developed between them and humans. Alexandra Horowitz, a cognitive scientist at Barnard College and the author of Inside of a Dog: What Dogs See, Smell and Know, has suggested that when humans and wolves first came into contact, only the affable animals had the temperament to earn the humans' trust, and they, in turn, were rewarded with food that the humans did not want to eat. Once dogs became comfortable in our company, humans sped up their social evolution by giving extra food to helpful dogs — ones that barked to warn of danger, for example. These, in turn, got more rewards and eventually became partners with humans, helping with hunts or herding other animals. Jack Russell terriers, like Ringo, above, a 3-year-old male, were ultimately bred for the very specific task of hunting foxes.